<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <title>Document</title>
</head>
<body>
  <script>
    var str = 'test@qq.com';
    var reg = /[@\.]/;
    var split_res = str.split(reg);
    console.log(split_res);   // 输出结果：(3) ["test", "qq", "com"]

    var str = 'We are a family';
    var reg = /\s/;
    var split_res = str.split(reg, 2);
    console.log(split_res);   // 输出结果：(2) ["We", "are"]
  </script>
</body>
</html>